| 摘要 |
PURPOSE: To prevent unnecessary image formation by providing a means which detects a supplied transfer material being a transparent sheet and a means which inhibits both-surface printing when the transparent sheet is detected. CONSTITUTION: A both-surface mode signal RY1 and a both-surface inhibition signal RY2 are used and when a normal opaque transfer material is supplied, the signal RY2 is held at 'H' by an I/O port 501. In this case, the output of an AND circuit 502 depends upon the signal RY1 and when the signal RY1 is at 'H', a current flows to a coil 504, so that a flapper is positioned as specified and enters both-surface mode. When the signal RY1 is at 'L', on the other hand, no current flows to the coil 504 and the flapper is positioned as specified and enters one-surface mode. When the transparent material transparency detecting means detects the transparent sheet, the signal RY2 is controlled to 'L' by the I/O port 501 and the output of the AND circuit 502 is fixed at 'L', so that the flapper is fixed at a specific position and enters used surface inhibition mode. |
